Bullet-probe.



G. E. MARSHALL.

BULLET PROBE.

APPLICATION I'ILED MAY 8, 1907.

Patented Nov. 3, 1908.

[NVENTOR WITNESSES aizf, @WM 8 4/} 414m Alla/120v v GEORGE E. MARSHALL, OF AGUILAR, COLORADO.

BULLE T-PROBE To all whom it may concern:

Be it known that I, GEORGE E. MARSHALL, citiyen of the United States, residing at Aguilar, in the county of Las-Animas and State of Colorado, have invented certain new and useful Improvements in Bullet- Probes of which the following is a specification.

This invention relates to that class of surgical probes known as bullet probes, and it has for its object a probe of this class so constructed and arranged with its adjuncts, that a visual signal will be given the operating surgeon when the probe encounters the bullet sought for.

Said inventlon consists of certain features or instrumentalities substantially as hereinafter fully disclosed and defined by the claim.

In the accompanying drawings Figure 1 is a view in side elevation of a probe embodying my invention connected up to a battery having a small incandescent lamp in its circuit. Fig. 2 is a longitudinal section of the probe on a larger scale. Fig. 3 is a detail of the electrodes, binding posts and connecting wires, detached from the probe body.

As is well known, much difliculty, discomfort and even danger to life accompanies the use of probes, particularly in cases where the surgeon is searching fora bullet, or

other metallic substance projected into a human body, sincereliance has been mainly placed on delicacy of touch or feel when the probe encounters a solid object, and in probing for bullets the probe has been liable to encounter the splinter of a bone, which may mislead the surgeon in his work.

My invention comprises a probe, either rigid, or flexible to follow the sinuous course of a bullet, consisting of a probe body A,

provided at the, point a with electrodes B, B which are connected through the probe by conducting wires C G with bind ing posts D D embedded in the head of a probe body, as shown.

. The binding posts are designed for con--- nection with a battery. T through its conductors E and E, and included in the battery circuit is a small incandescent lamp F, the film of which will glow in response to a current of low voltage. 1 I

Specification of Letters Patent.

, Application filed May 8, 1907. Serial No. 372,508.

Patented Nov. 3, 1908.

The metallic electrodes B B, as shown form at their outer ends suitably shaped bodies, their inner ends being shaped, as shown to be inclosed by the point end a of the probe-body A, and being grooved, as at b b to receive the material of the probe body whereby the parts are rigidly united.

The electrodes B B are insulated from each other by a plate G of hard rubber, or it may be that in manufacture, the body of the probe being of rubber, the electrodes may be properly spaced apart and the body .A molded about and between them.

The body A of the probe is formed of staff, but is preferably vulcanized to form a flexible staff in order that it may follow the sinuous track of a bullet entering the body. Embedded within the body A of the probe and insulated from each other thereby are conducting wires O C leading from the electrodes B B to binding posts D D located in the head a of the probe.

The binding posts are adapted to receive the terminals 6 e of conductors E E leading from the poles of battery T, and included in the circuit of the battery is an incandescent lamp F giving a glow in response to a current of low voltage.

The current from the battery is so regulated by resistances, or otherwise, that no current will flow when the electrodes at the point of the probe are in contact with the bones or tissues or internal fluids of the body, the conductivitythereof being not sufficient to excite the flow, but upon encountering a bullet, or other metal,the circuit will be closed, and the lamp indicate to the surgeon that metal has been found.

- connections between said binding posts and said battery, a low-voltage incandescent fila- In testimony whereof I afiix my. signature, ment-lamp arranged in said electrical conin presence of two Witnesses.

nections and a current-regulating resistance arranged in the latter for interrupting the flow of any current when said electrodes Witnesses-z contact with the bones of the body as in the GEORGE W. NORMAN, probing operation. v HARRY O. Cossmvr.

GEORGEJE. MARSHALL. 

